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                                                                     EXHIBIT 4.1


                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                             ASPEN TECHNOLOGY, INC.

             PURSUANT TO SECTION 242 OF THE GENERAL CORPORATION LAW
                            OF THE STATE OF DELAWARE

                ------------------------------------------------

     Aspen Technology, Inc., a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware (the
"Corporation"), does hereby certify as follows:

     At a meeting of the Board of Directors of the Corporation a resolution was
duly adopted, pursuant to Section 242 of the General Corporation Law of the
State of Delaware, setting forth an amendment to the Certificate of
Incorporation of the Corporation, as amended to date, and declaring said
amendment to be advisable. The stockholders of the Corporation duly adopted said
amendment at a special meeting of stockholders in accordance with Section 242 of
the General Corporation Law of the State of Delaware. The resolution setting
forth the amendment is as follows:

RESOLVED: That Article FOURTH of the Certificate of Incorporation of the
          Corporation, as amended, be deleted in its entirety and the following
          paragraphs shall be inserted in lieu thereof:

          "FOURTH: That, effective at 5:00 pm., eastern time, on the filing
          date of this Certificate of Amendment of Certificate of
          Incorporation, as amended (the "Effective Time"), a one-for-three
          reverse stock split of the Corporation's common stock shall become
          effective, pursuant to which each three shares of common stock
          outstanding and held of record by each stockholder of the
          Corporation (including treasury shares) immediately prior to the
          Effective Time shall be reclassified and combined into one share of
          common stock automatically and without any action by the holder
          thereof upon the Effective Time and shall represent one share of
          common stock from and after the Effective Time. No fractional
          shares of common stock shall be issued as a result of such
          reclassification and combination. In lieu of any fractional shares
          to which the stockholder would otherwise be entitled, the
          Corporation shall pay cash equal to such fraction multiplied by the
          then fair market value of the common stock as determined by the
          Board of Directors of the Corporation.

          The Corporation is authorized to issue two classes of capital
          stock, one of which is designated as common stock, $.001 par value
          per share ("Common Stock"), and the other of which is designated as
          preferred stock, $0.10 par value per share ("Preferred Stock"). The
          total number of shares of both classes of capital stock that the
          Corporation shall have authority to issue is 110,000,000 shares,
          consisting of 100,000,000 shares of Common Stock and 10,000,000
          shares of Preferred Stock. The following is a statement of the
          designations and the powers, preferences and rights of, and the
          qualifications, limitations or restrictions applicable to, each
          class of capital stock of the Corporation."

     IN WITNESS WHEREOF, the Corporation has caused this Certificate of
Amendment to be signed by its President and Chief Executive Officer as of
_________, 2003.

                                     ASPEN TECHNOLOGY, INC.

                                     By:
                                        ----------------------------------------
                                        David L. McQuillin
                                        President and Chief Executive Officer